Clean Nailon siding easily with just a soft bristle brush and a garden hose. Live where soil gets caked on? Dissolve 1/3 cup detergent (Tide, for example), and 2/3 cup trisodium (Soilax, for example) into 4 quarts water. Mildew a problem? Trade one quart of 5% sodium hydrochloride (Clorox bleach, for example) instead of one quart of water in your mix.
When the exterior of your home or building is unusually dirty, wash from the top and work your way down to the bottom of your structure. Then brush or spray on cleaning solution. After several minutes dirt should be loose and rinse away easily. To avoid stains and streaks all siding must be rinsed thoroughly. NEVER power wash or pressure wash your Nailon panels; doing this weakens them and does not extend their life for maximum use. With proper attention, however, you can use your Nailon siding for years to come.
MAKE SURE to observe and obey all safety rules and recommendations set forth by tool manufacturers and local, state, and federal authorities for any building project including all applicable building codes.